Two teenagers have been confirmed as among the Britons to have been killed in the Sri Lanka terror attacks on Easter Sunday.
Eight British nationals died when suicide bombers targeted churches and hotels, killing at least 310 people at eight locations.
It was unclear if any Britons are among the 500 injured in the explosions.
Family members have paid tribute to the UK victims that have been identified so far.
Daniel and Amelie Linsey
The brother and sister were killed on the final day of their holiday in the South Asian country.
Daniel, 19, and Amelie, 15, were reportedly in a cafe in the Shangri-La Hotel which was targeted by the bombers.
The pair from London were on holiday with their father Matthew Linsey, an investor in emerging markets.
He told The Times his children were born in Britain but had dual US-UK citizenship because he was born in the US.
Mr Linsey, 60, told the paper: "Amelie was really fun. She was smart, beautiful.
"Very loving, very caring, understanding.
"She cared about her family and her friends. And the same with Danny."
Their brother David wrote in a Facebook post: "Thank you to those who have given their support and prayers.
"It has meant a lot us."
Bill Harrop and Sally Bradley
The married couple were staying at the Cinnamon Grand Hotel where they were killed on Sunday.
Mr Harrop, a retired firefighter, and Ms Bradley, a doctor, were holidaying in the country.
The couple reportedly relocated to Western Australia from Manchester after Mr Harrop retired from the fire service in 2012.
David Keelan, assistant county fire officer at Greater Manchester Fire and Rescue Service, said news of his former colleague's death was "devastating".
He added: "Bill served here for 30 years, retiring at the end of 2012.
"He was a much loved and respected colleague and friend. He will be greatly missed."
Michael McLean, a retired fire officer, told Sky News he knew Bill from the fire service. He said: "They were a close and devoted couple.
"Billy was a larger than life character who was a generous person. His sons were very important to him.
"At work he rose through the ranks to become the borough commander in Manchester city centre. In that role, he was involved in a lot of partnership work to reduce fires and the consequences of fire. For a period, Sally was head of public health in Manchester so they both had senior roles in public health and fire safety."
He added: "They only went to Oz as Sally got a job at a hospital in Freemantle. She was a GP in the UK, but had retired."
He saw them three years ago, on a visit to Perth.
He said: "Sally had a job at the local hospital and they lived in Freemantle at the time. We met up for dinner one evening and they were both happy and healthy.
"A few days later, Bill picked me up and drove us to the coast where we had lunch overlooking the Indian Ocean. He later dropped me off at my hotel in Perth. That is the last time I saw him alive. Really tragic they have been taken so early."
Ms Bradley began her career as a GP in Salford before moving on to become a director of public health in Manchester.
She continued to practise medicine after moving to Australia.
Her family said in a statement: "She was the personification of joy that life could bring if you approached it with a smile on your face and warmth in your heart."
Ms Bradley's brother Lord Keith Bradley said: "I have lost a sister, who was not only an inspiration to me, but someone that was respected and loved across Greater Manchester.
"Over the last 24 hours I have been inundated with beautiful tributes to a remarkable and wondrous woman."
Anita, Alex and Annabel Nicholson
British lawyer Ben Nicholson confirmed the deaths of his "perfect wife" and "amazing" children after the terror attacks.
Mr Nicholson was waiting for breakfast with Anita, 42, Alex, 14, and Annabel, 11, when the Shangri-La Hotel in Colombo was targeted.
He added that the attack happened as the family were sitting at their restaurant table.
Mr Nicholson said: "Mercifully, all three of them died instantly and with no pain or suffering."
His statement continued: "I am deeply distressed at the loss of my wife and children.
"Anita was a wonderful, perfect wife and a brilliant, loving and inspirational mother to our two wonderful children.
"The holiday we had just enjoyed was a testament to Anita's enjoyment of travel and providing a rich and colourful life for our family, and especially our children.
"Alex and Annabel were the most amazing, intelligent, talented and thoughtful children and Anita and I were immensely proud of them both and looking forward to seeing them develop into adulthood.
"They shared with their mother the priceless ability to light up any room they entered and bring joy to the lives of all they came into contact with."
The family lived in Singapore where Ms Nicholson worked as managing counsel for mining company Anglo American.
The identity of the eighth British victim is yet to be confirmed.
Police have arrested 40 suspects after the attacks, including the driver of a van allegedly used by the suicide bombers and the owner of a house where some of them are believed to have lived.
The bombing victims include at least 31 foreigners from at least 12 countries.
Danish billionaire and ASOS' largest shareholder Anders Holch Povlsen lost three children in the attacks.
His family were on a trip to Sri Lanka as the co-ordinated attacks took place.
Labour MP Tulip Siddiq said on Twitter she has lost a relative in the attacks.
She wrote: "It's all so devastating. Hope everyone is keeping safe.
"Solidarity with the people of Sri Lanka."
Another victim was a young woman who studied at the University of London.
Nisanga Mayadunne, from Sri Lanka, and her mother Shantha reportedly died at the Shangri-La hotel.
The former UK student posted a photo of her eating breakfast with her family hours before the blast.